Encyclopedia Home / U / Unstable angina

Unstable angina

  • Definition

    Unstable angina is a condition in which your heart doesn't get enough blood flow and oxygen. It may lead up to a heart attack.

    Angina is a type of chest discomfort caused by poor blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).

    See also:

    • Stable angina
    • Variant angina

    Alternative Names

    Accelerating angina; New-onset angina; Angina - unstable; Progressive angina

    Causes, incidence, and risk factors

    Coronary artery disease due to atherosclerosis is by far the most common cause of unstable angina. Atherosclerosis is the buildup of fatty material called plaque along the walls of the arteries. This causes arteries to become narrowed and less flexible, which interrupts blood flow to the heart, causing chest pain.

    People with unstable angina are at increased risk of having a heart attack.

    Coronary artery spasm is a rare cause of angina.

    Risk factors for coronary artery disease include:

    • Diabetes
    • Family history of early coronary heart disease -- a close relative such as a sibling or parent had heart disease before age 55 (in a man) or before age 65 (in a woman)
    • High blood pressure
    • High LDL cholesterol
    • Low HDL cholesterol
    • Male gender
    • Not getting enough exercise
    • Obesity
    • Older age
    • Smoking